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%I #8 Jan 15 2024 13:37:02
%S 12,18,30,42,102,138,282,618,642,822,1698,1878,2082,2238,2382,2658,
%T 2802,3462,3558,3918,4638,4722,5442,6198,6702,8538,8598,9678,10938,
%U 12162,12378,12822,12918,13218,13722,13758,13998,14082,16062,17418,19542
%N Numbers that are divisible by exactly 3 primes (counted with multiplicity) and sandwiched between primes.
%C There are 106 of these numbers below 10^5.
%e 12 is a term: 12 = 2*2*3, and 11 and 13 primes.
%t Select[Range[9! ],Plus@@Last/@FactorInteger[ # ]==3&&PrimeQ[ #-1]&&PrimeQ[ #+1]&]
%Y Cf. A014612.
%Y Equals 6*A060212. - _Zak Seidov_ and _Esko Ranta_, Dec 06 2009
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Dec 04 2009